使用Perspective Broker进行扭曲身份验证

时间:2011-07-19 18:00:38

标签: python twisted

一直在学习Tvisted周,读过这本书和大部分码头,但我无法理解单一时刻。来自Twisted文档 http://twistedmatrix.com/documents/10.1.0/core/howto/pb-cred.html 服务器

#!/usr/bin/env python

# Copyright (c) 2009 Twisted Matrix Laboratories.
# See LICENSE for details.

from zope.interface import implements

from twisted.spread import pb
from twisted.cred import checkers, portal
from twisted.internet import reactor

class MyPerspective(pb.Avatar):
    def __init__(self, name):
        self.name = name
    def perspective_foo(self, arg):
        print "I am", self.name, "perspective_foo(",arg,") called on", self

class MyRealm:
    implements(portal.IRealm)
    def requestAvatar(self, avatarId, mind, *interfaces):
        if pb.IPerspective not in interfaces:
            raise NotImplementedError
        return pb.IPerspective, MyPerspective(avatarId), lambda:None

p = portal.Portal(MyRealm())
c = checkers.InMemoryUsernamePasswordDatabaseDontUse(user1="pass1",
                                                     user2="pass2")
p.registerChecker(c)
reactor.listenTCP(8800, pb.PBServerFactory(p))
reactor.run()

客户端

#!/usr/bin/env python

# Copyright (c) 2009 Twisted Matrix Laboratories.
# See LICENSE for details.

from twisted.spread import pb
from twisted.internet import reactor
from twisted.cred import credentials

def main():
    factory = pb.PBClientFactory()
    reactor.connectTCP("localhost", 8800, factory)
    def1 = factory.login(credentials.UsernamePassword("user1", "pass1"))
    def1.addCallback(connected)
    reactor.run()

def connected(perspective):
    print "got perspective1 ref:", perspective
    print "asking it to foo(13)"
    perspective.callRemote("foo", 13)

main()

如果用户输入了错误的密码:

Unhandled Error
Traceback (most recent call last):
Failure: twisted.cred.error.UnauthorizedLogin: 

我代替例外,告诉用户他没有输入正确的密码?\ bad username

我试图改变:

c = checkers.InMemoryUsernamePasswordDatabaseDontUse(user1="pass1",user2="pass2") 
p.registerChecker(c)

on

passwords = {
    'admin': 'aaa',
    'user1': 'bbb',
    'user2': 'ccc'
    }
p.registerChecker(PasswordDictChecker(passwords))
class PasswordDictChecker(object):
    implements(checkers.ICredentialsChecker)
    credentialInterfaces = (credentials.IUsernamePassword,)

    def __init__(self, passwords):
        "passwords: a dict-like object mapping usernames to passwords"
        self.passwords = passwords

    def requestAvatarId(self, credentials):
        username = credentials.username
        if self.passwords.has_key(username):
            if credentials.password == self.passwords[username]:
                return defer.succeed(username)
            else:
                return defer.fail(
                    credError.UnauthorizedLogin("Bad password"))
        else:
            return defer.fail(
                credError.UnauthorizedLogin("No such user"))

但是出现了错误,我认为这是错误的方式。

P.S。我知道如何在没有Perspective Broker的情况下进行身份验证...

1 个答案:

答案 0 :(得分:0)

如果要实施重试,请在客户端完全执行。您应该更改服务器以报告“密码错误”或“没有此类用户”等消息,因为这些信息会泄露给攻击者。

要让客户端重试,请在登录时添加一个errback,提示输入新密码(可能是新用户)并再次调用login。